The invention relates to an analysis device provided with a pump which is connected, via a pump line, to a multi-way valve, a first and second discharge line, which are connected to the multi-way valve and can be connected to the analysis vessel, a first feed line, which is connected to the multi-way valve, for feeding a sample to be analysed to the multi-way valve, a second feed line, which is connected to the multi-way valve or to the pump, for feeding a reactant to the multi-way valve, a flushing line which is connected to the multi-way valve, it being possible to place the discharge lines, the first feed line and the flushing line in fluid communication with the pump line via the valve, as well as an operating device for controlling the pump and the multi-way valve.